I've just watched the game on delay and I can't understand the Onomah comments at all, I can only think that some are expecting the world from him in 7 minutes. He's come on at a time where the game is done and it's two teams playing out the final stages. In that time he chased down and made two successful challenges that resulted in attacks, he drew a free-kick in the final third, never lost the ball completing all of his passes and had a shot blocked. Nothing spectacular but I don't see what he did in that time to deserve comments saying he was the only disappointment of the night? I just think it's beyond ridiculous if I'm being honest. Nothing about Alli, Kane or Son who was pretty poor when he came on, just focusing on Onomah not tearing it up.
I think where the problem lies is that those who haven't seen him before are expecting a completely different kind of player to what he actually is. Pochettino brings him on in forward positions so fans are expecting someone that's going to run at defences, attack and score goals like a Marcus Rashford type player but that's not his game at all. Imagine Dembele but as a physically slight 19 year old, that's basically what Josh is. He's a deep-lying central midfielder but Poch obviously doesn't think he's ready for that level of responsibility yet so he plays him higher up the field where any mistake is less likely to be a fatal one. Spurs fans like to preach that Poch knows best so maybe just back him on this one and give the kid time and support.